1. Field of the Invention
The present invention relates to an ink jet recording apparatus including an ink jet recording head and a driver circuit device which drives or operates the ink jet recording head.
2. Related Art Statement
There is known an ink jet recording apparatus which includes a carriage and an ink jet recording head mounted on the carriage and which reciprocates the carriage in directions perpendicular to a direction in which a recording medium is fed, while the ink jet recording head ejects droplets of ink toward the recording medium so as to record an image on the recording medium. This ink jet recording apparatus further includes a driver circuit device which is mounted on the carriage and which outputs a drive signal to drive the ink jet recording head so that the recording head ejects, based on the drive signal, the droplets of the ink toward the recording medium.
However, when the driver circuit device outputs the drive signal to the ink jet recording head, a great electric current momentarily flows in the driver circuit device, whereby a temperature of the driver circuit device abruptly increases. In addition, since the driver circuit device includes a plurality of driver elements corresponding to a plurality of ink ejection nozzles, there is a tendency that the total number, and density, of the driver elements increase. Thus, if the ink jet recording head continues, for a long time, ejecting concurrently respective droplets of ink from the nozzles, the temperature of the recording head significantly increases. This temperature increase may cause malfunction or instability of the driver circuit device, which in turn may cause unstable ejection of the ink from the recording head. Hence, there has been practiced to mount a heat radiator on the carriage, such that the heat radiator is held in contact with the driver circuit device, so that the heat generated by the driver circuit device is radiated by the heat radiator and accordingly the driver circuit device is cooled down.
Japanese Patent No. 2,927,141 discloses an invention in which an electric fan is used to radiate heat which is generated by a driver circuit device and is conducted by a heat pipe.